API reference
Files API

Files API

Upload once, reuse across requests with file_id in document or image content blocks.

This API is compatible with Anthropic's Files beta concepts and works across our router. Files are scoped to your API key and cannot be accessed by other users.

Endpoints

  • POST /api/anthropic/v1/files – upload via multipart/form-data (file) or JSON { content, filename, mime_type }
  • GET /api/anthropic/v1/files – list files
  • GET /api/anthropic/v1/files/{id} – get file metadata
  • DELETE /api/anthropic/v1/files/{id} – delete a file
  • GET /api/anthropic/v1/files/{id}/content – download content (returns raw bytes for base64 uploads)

Headers

  • x-api-key: $API_KEY or Authorization: Bearer $API_KEY
  • Optional: anthropic-version: 2023-06-01
  • Optional: anthropic-beta: files-api-2025-04-14

Upload

Multipart (recommended):

curl -X POST https://api.kushrouter.com/api/anthropic/v1/files \
  -H "x-api-key: $API_KEY" \
  -H "anthropic-version: 2023-06-01" \
  -F "file=@/path/to/document.pdf"

JSON:

curl -X POST https://api.kushrouter.com/api/anthropic/v1/files \
  -H "x-api-key: $API_KEY" \
  -H "content-type: application/json" \
  -d '{
    "content": "data:application/pdf;base64,....",
    "filename": "paper.pdf",
    "mime_type": "application/pdf"
  }'

List

curl -s https://api.kushrouter.com/api/anthropic/v1/files \
  -H "x-api-key: $API_KEY"

Get metadata

curl -s https://api.kushrouter.com/api/anthropic/v1/files/file_123 \
  -H "x-api-key: $API_KEY"

Download content

curl -s -L https://api.kushrouter.com/api/anthropic/v1/files/file_123/content \
  -H "x-api-key: $API_KEY" -o out.bin

If the file was uploaded as base64 (e.g., data:application/pdf;base64,...), the router will decode and return raw bytes with the correct Content-Type.

Delete

curl -X DELETE https://api.kushrouter.com/api/anthropic/v1/files/file_123 \
  -H "x-api-key: $API_KEY"

Using files in messages

Reference the uploaded file via file_id in an Anthropic Messages request.

Security

  • Files are always scoped to your API key and cannot be accessed by other users.
  • Download and metadata routes verify ownership using your API key.
  • The streaming endpoints (Edge) do not access storage directly; they call these Node-based routes with your API credentials.
BatchesWebhooks